Illuminating the landscape of sibling relationship quality: An evidence and gap map.

This paper used an evidence and gap map (EGM) to advance the scientific understanding of sibling relationship quality among children aged 2 to 18 years by synthesizing literature on 277 empirical studies from 1985 to 2022 to delineate patterns of study design, sampling, and measurement. Most existing research has utilized majority of White, middle-to-upper class, and/or two-caregiver family samples. Nearly 85% (n = 235) of studies used quantitative methods to measure sibling relationship quality across eight domains: conflict, warmth/affection, quality, cohesion, hostility, power/control, positive engagement, and conflict management. A total of 122 studies used a measure of sibling relationship quality as a predictor of sibling behavior, social, psychological, cognitive, health, or physiological outcomes. Future directions for research are discussed.